Communication Apparatus

ABSTRACT

A communication apparatus may receive a first specific signal including a specific wireless identifier from an external apparatus; determine whether the specific wireless identifier is a first wireless identifier; in a case where it is determined that the specific wireless identifier is the first wireless identifier, shift an operating state of the communication apparatus to one state of a first parent state and a child state, and form the first wireless network to which both the communication apparatus and the external apparatus belong. In a case where it is determined that the specific wireless identifier is not the first wireless identifier, the communication apparatus is maintained in a first non-belonging state. The communication apparatus may receive specific wireless setting information from the external apparatus by using the first wireless network; and belong to the specific wireless network by using the specific wireless setting information.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of prior U.S. application Ser. No.15/198,612, filed Jun. 30, 2016, which claims priority to JapanesePatent Application No. 2015-134027, filed on Jul. 3, 2015, the entirecontents of which are hereby incorporated by reference into the presentapplication.

TECHNICAL FIELD

The present specification discloses a technique for a communicationapparatus to form a wireless network.

DESCRIPTION OF RELATED ART

Various techniques for a communication apparatus to form a wirelessnetwork are known. For example, a communication apparatus supporting aso-called SoftAP function can activate a SoftAP and operate as a parentstation of a wireless network. In this case, when another apparatusoperates as a child station of the wireless network, both thecommunication apparatus and the other apparatus can belong to thewireless network. In addition, a communication apparatus supporting theWFD (an abbreviation of Wi-Fi Direct (registered trademark)) schemeformulated by the Wi-Fi Alliance can shift to a G/O (an abbreviation ofGroup Owner) state in accordance with the WFD scheme and operate as aparent station of a wireless network. In this case, when anotherapparatus operates as a child station of the wireless network (forexample, in a Client state in accordance with the WFD scheme), both thecommunication apparatus and the other apparatus can belong to thewireless network.

SUMMARY

A communication apparatus can operate as a parent station (for example,a SoftAP or a G/O apparatus in accordance with the WFD scheme describedabove) or a child station in response to, for example, receiving awireless connection request from another apparatus and can belong to awireless network. However, since a communication apparatus is incapableof appropriately determining a network to which the communicationapparatus should belong, the communication apparatus may end upbelonging to a wireless network not desired by a user. When thecommunication apparatus belongs to the wireless network not desired bythe user, a processing load on the communication apparatus mayunnecessarily increase. The present specification provides a techniquecapable of preventing a processing load on a communication apparatusfrom increasing unnecessarily by causing the communication apparatus toappropriately determine a wireless network to which the communicationapparatus should belong.

A communication apparatus disclosed in the present specification maycomprise: a processor; and a memory storing a specific character stringand computer-readable instructions therein, the computer-readableinstructions, when executed by the processor, causing the communicationapparatus to perform: receiving a first specific signal including aspecific wireless identifier from an external apparatus; determiningwhether the specific wireless identifier in the first specific signal isa first wireless identifier including the specific character string inthe memory, the first wireless identifier being for identifying a firstwireless network; in a case where it is determined that the specificwireless identifier is the first wireless identifier, shifting anoperating state of the communication apparatus from a firstnon-belonging state in which the communication apparatus does not belongto the first wireless network to a first parent state in which thecommunication apparatus operates as a parent station of the firstwireless network; and forming the first wireless network to which boththe communication apparatus being the parent station and the externalapparatus being a child station belong after the operating state of thecommunication apparatus is shifted to the first parent state, wherein ina case where it is determined that the specific wireless identifier isnot the first wireless identifier, the communication apparatus ismaintained in the first non-belonging state.

A communication apparatus disclosed in the present specification maycomprise: a processor; and a memory storing a specific character stringand computer-readable instructions therein, the computer-readableinstructions, when executed by the processor, causing the communicationapparatus to perform: receiving a first specific signal including aspecific wireless identifier from an external apparatus; determiningwhether the specific wireless identifier in the first specific signal isa first wireless identifier including the specific character string inthe memory, the first wireless identifier being for identifying a firstwireless network; in a case where it is determined that the specificwireless identifier is the first wireless identifier, shifting anoperating state of the communication apparatus from a firstnon-belonging state in which the communication apparatus does not belongto the first wireless network to one state of a first parent state inwhich the communication apparatus operates as a parent station of thefirst wireless network and a child state in which the communicationapparatus operates as a child station of the first wireless network;forming the first wireless network to which both the communicationapparatus being the parent station or the child station and the externalapparatus being the child station or the parent station belong after theoperating state of the communication apparatus is shifted to either ofthe first parent state or the child state, wherein in a case where it isdetermined that the specific wireless identifier is not the firstwireless identifier, the communication apparatus is maintained in thefirst non-belonging state; receiving specific wireless settinginformation from the external apparatus by using the first wirelessnetwork in a case where the first wireless network is formed, thespecific wireless setting information being currently used in a specificwireless network formed by a specific access point, the externalapparatus satisfying either one condition of currently belonging to thespecific wireless network and having previously belonged to the specificwireless network; and belonging to the specific wireless network byusing the specific wireless setting information in a case where thespecific wireless setting information is received from the externalapparatus.

A control method and a computer program for realizing such acommunication apparatus and a computer-readable storage medium thatstores the computer program are also novel and useful. In addition, acommunication system including the communication apparatus and theexternal apparatus described above is also novel and useful.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows a configuration of a communication system;

FIG. 2 is a sequence diagram of a first embodiment in which a printeroperates as a SoftAP;

FIG. 3 is a sequence diagram that is a continuation of FIG. 2;

FIG. 4 is a sequence diagram of a second embodiment in which a printeroperates as a G/O in accordance with the WFD scheme;

FIG. 5 is a sequence diagram that is a continuation of FIG. 4; and

FIG. 6 is a sequence diagram of a third embodiment in which a printeroperates as a child station.

EMBODIMENTS First Embodiment

(Configuration of Communication System 2; FIG. 1)

The communication system 2 comprises a printer 10, a terminal apparatus50, and a normal access point 100. Hereinafter, the normal access point100 will be referred to as a “normal AP” 100.

(Configuration of Printer 10)

The printer 10 is a peripheral apparatus capable of performing aprinting function (that is, a peripheral apparatus such as the terminalapparatus 50). The printer 10 includes an operating unit 12, a displayunit 14, a print performing unit 16, a wireless interface 20, and acontroller 30. Hereinafter, an interface will be abbreviated as an“I/F”.

The operating unit 12 comprises a plurality of keys. By operating theoperating unit 12, the user can input various instructions to theprinter 10. The display unit 14 is a display for displaying varioustypes of information. The print performing unit 16 comprises a printingmechanism such as an inkjet system, a laser system, or the like.

The wireless I/F 20 is an I/F for performing wireless communication inaccordance with the Institute of Electrical and Electronics Engineers,Inc. (IEEE) 802.11. Specifically, the wireless I/F 20 can establish awireless connection with the normal AP 100 (hereinafter, referred to asa “normal AP connection”) in accordance with IEEE 802.11 and, as aresult, the printer 10 can join, as a child station, a wireless networkin which the normal AP 100 operates as a parent station (hereinafter,referred to as a “normal APNW” (an abbreviation of normal AP network)).In addition, the printer 10 can perform wireless communication withother apparatus(es) belonging to the normal APNW (for example, theterminal apparatus 50) via the normal AP 100.

The wireless I/F 20 particularly supports a SoftAP (an abbreviation ofsoftware access point) function in the IEEE 802.11. When the SoftAP ofthe wireless I/F 20 is activated, the printer 10 operates as an AP (thatis, a parent station) of a wireless network and is able to establish awireless connection (hereinafter, referred to as a “SoftAP connection”)with another apparatus (for example, the terminal apparatus 50). Thatis, the other apparatus(es) can join, as a child station, a wirelessnetwork (hereinafter, referred to as a “SoftAPNW” (an abbreviation of aSoftAP Network)) in which the printer 10 operates as a parent station.

Physically, the wireless I/F 20 is a single interface. However, a firstMAC address for establishing a normal AP connection and a second MACaddress for establishing a SoftAP connection (that is, a MAC addressthat differs from the first MAC address) are assigned to the wirelessI/F 20. Therefore, the printer 10 is capable of simultaneouslyperforming both wireless communication using the normal AP connectionand wireless communication using the SoftAP connection via the wirelessI/F 20. Moreover, in a modification, an interface for performingwireless communication using the normal AP connection and an interfacefor performing wireless communication using the SoftAP connection may berespectively configured by chips that physically differ from each other.

The controller 30 comprises a CPU 32 and a memory 34. The CPU 32 is aprocessor that performs various processes in accordance with a program36 stored in the memory 34. The memory 34 is configured by a RAM, a ROM,or the like. The program 36 includes initial SoftAP setting information38 and alternative SoftAP setting information 40.

The initial SoftAP setting information 38 is information used in aSoftAPNW formed by a SoftAP (hereinafter, referred to as an “initialSoftAP”) that is activated at a timing where power of the printer 10 isturned on. The initial SoftAP setting information 38 is informationprovided to a vendor of the printer 10 in advance by a specific businessoperator which differs from the vendor. The initial SoftAP settinginformation 38 includes an SSID (an abbreviation of a service setidentifier) “XXX”, a password “AAA”, and the like.

The alternative SoftAP setting information 40 is information used in aSoftAPNW formed by a SoftAP (hereinafter, referred to as an “alternativeSoftAP”) that is activated at a different timing from the timing wherepower of the printer 10 is turned on. The alternative SoftAP settinginformation 40 is information determined in advance by the vendor of theprinter 10 and differs from the initial SoftAP setting information 38.The alternative SoftAP setting information 40 includes an SSID “YYY”, apassword “BBB”, and the like. Hereinafter, the SoftAPNW in which theinitial SoftAP setting information 38 is used and the SoftAPNW in whichthe alternative SoftAP setting information 40 is used will berespectively referred to as an “initial SoftAPNW” and an “alternativeSoftAPNW”.

The memory 34 comprises a parent station setting area 44 and a normal APsetting area 46. The parent station setting area 44 is an area in which,in a state where the printer 10 operates as a parent station of aSoftAPNW, wireless setting information used in the SoftAPNW (that is,the initial SoftAP setting information 38 or the alternative SoftAPsetting information 40) is stored. The normal AP setting area 46 is anarea in which, in a state where the printer 10 operates as a childstation of a normal APNW, wireless setting information used in thenormal APNW (that is, an SSID, a password, and the like; hereinafter,referred to as “normal AP setting information”) is stored.

(Configuration of Normal AP 100)

The normal AP 100 is a known AP that is referred to as a wireless AP, awireless LAN router, or the like, and differs from the SoftAP. Thenormal AP 100 relays communication between a pair of apparatuses forwhich a normal AP connection with the normal AP 100 has been establishedor, that is, communication between the pair of child stations of thenormal APNW (for example, the printer 10 and the terminal apparatus 50).The normal AP 100 stores normal AP setting information 150 currentlyused in the normal APNW. The normal AP setting information 150 includesan SSID “ZZZ” and a password “CCC”.

(Configuration of Terminal Apparatus 50)

The terminal apparatus 50 is, for example, a portable terminal such as amobile phone, a smart phone, a notebook PC, or a tablet PC. The terminalapparatus 50 can join the normal APNW or a SoftAPNW as a child station.The terminal apparatus 50 stores the normal AP setting information 150in a case where the terminal apparatus 50 currently belongs to thenormal APNW or in a case where the terminal apparatus 50 has previouslybelonged to the normal APNW. The terminal apparatus 50 also stores anapplication program (hereinafter, referred to as a “settingapplication”) 200 for setting the normal AP setting information 150 tothe printer 10. The setting application 200 is a program provided by thevendor of the printer 10 and includes information 40 which matches thealternative SoftAP setting information 40 stored in the printer 10 inadvance.

(Processes of Respective Devices 10, 50, 100, and the Like: FIGS. 2 and3)

Next, contents of the respective processes performed by the printer 10and the like will be described with reference to FIGS. 2 and 3. In aninitial state shown in FIG. 2, the terminal apparatus 50 has establisheda normal AP connection with the normal AP 100 and belongs to a normalAPNW. In T10, the user turns on power of the printer 10. Hereinafter,when describing processes performed by the CPU 32 of the printer 10, anexpression “the printer 10 performs . . . ” will be used in place of anexpression “the CPU 32 of the printer 10 performs . . . ”.

In T12, the printer 10 activates the initial SoftAP using the initialSoftAP setting information 38. Specifically, the printer 10 stores theinitial SoftAP setting information 38 included in the program 36 in theparent station setting area 44. Accordingly, an operating state of theprinter 10 shifts from a state where the printer 10 does not belong tothe initial SoftAPNW to a parent state where the printer 10 operates asa parent station of the initial SoftAPNW.

A reason for adopting a configuration in which the initial SoftAP isactivated when power of the printer 10 is turned on (hereinafter,referred to as a “specific configuration”) will now be described. First,the reason for activating the initial SoftAP is as follows. In theinitial SoftAPNW that is formed in accordance with the initial SoftAP,the initial SoftAP setting information 38 that is setting informationhaving an authentication scheme and a coding scheme of relatively lowsecurity levels is used. Accordingly, the user can have variousapparatuses join the initial SoftAPNW as child stations without havingto perform complicated wireless settings. In this case, the printer 10can perform wireless communication with the various apparatuses usingthe initial SoftAPNW. In this manner, the printer 10 activates theinitial SoftAP in order to enable communication with various apparatusesto be performed.

In addition, a reason why the initial SoftAP is activated when turningon power is as follows. Supposing that the initial SoftAP is notactivated when turning on power, the user must perform an operation foractivating the initial SoftAP after power has been turned on. On theother hand, in the case where the initial SoftAP is activated whenturning on power, since the user may not need to separately perform anoperation for turning on power and an operation for activating theinitial SoftAP, convenience is improved. The specific configuration isadopted due to the two reasons described above.

In a case where the user of the terminal apparatus 50 desires to havethe printer 10 also belong to the normal APNW to which the terminalapparatus 50 belongs, in T14, the user performs an operation foractivating the setting application 200 on the terminal apparatus 50.Accordingly, the terminal apparatus 50 activates the setting application200 and, in T16, reads the SSID “YYY” included in the alternative SoftAPsetting information 40 in the setting application 200, and transmits aProbe Request signal including the SSID “YYY” to the printer 10.Hereinafter, Request and Response will be respectively written as “Req.”and “Res.”.

In a case where the printer 10 receives the Probe Req. signal includingthe SSID “YYY” from the terminal apparatus 50, in T18, the printer 10determines whether or not the SSID “YYY” in the Probe Req. signalmatches the SSID “YYY” included in the alternative SoftAP settinginformation 40 in the memory 34. In a case where the SSID “YYY” in theProbe Req. signal matches the SSID “YYY” in the memory 34 (YES in T18),the printer 10 proceeds to T20.

On the other hand, for example, in a case where the user desires thatthe terminal apparatus 50 establish a wireless connection with an APother than the normal AP 100, the operation for activating the settingapplication 200 is not performed on the terminal apparatus 50 but anoperation for establishing the wireless connection with an AP other thanthe normal AP 100 is performed on the terminal apparatus 50. In thiscase, the printer 10 may receive a Probe Req. signal that does notinclude the SSID “YYY” from the terminal apparatus 50. In such a state,the printer 10 determines that the SSID in the Probe Req. signal doesnot match the SSID “YYY” in the memory 34 (NO in T18) and ends theprocessing shown in FIG. 2 without performing the processes of T20 andthereafter. In this case, the operating state of the printer 10 ismaintained in a state where the printer 10 does not belong to thealternative SoftAPNW identified by the SSID “YYY”.

In T20, the printer 10 stops the initial SoftAP. Specifically, theprinter 10 erases the initial SoftAP setting information 38 in theparent station setting area 44. Accordingly, the printer 10 causes theinitial SoftAPNW to disappear. The operating state of the printer 10shifts from a parent state where the printer 10 operates as the parentstation of the initial SoftAPNW to a state where the printer 10 does notbelong to the initial SoftAPNW. In the present embodiment, since theprinter 10 only has one MAC address (that is, a second MAC address) fora SoftAP, a state where both of the initial SoftAP and the alternativeSoftAP are simultaneously active cannot be constructed. In addition,since the alternative SoftAP needs to be activated in a subsequentprocess, in T20, the printer 10 stops the initial SoftAP.

In T22, the printer 10 activates the alternative SoftAP using thealternative SoftAP setting information 40. Specifically, the printer 10stores, in the parent station setting area 44, the alternative SoftAPsetting information 40 included in the program 36. Accordingly, theoperating state of the printer 10 shifts from the state where theprinter 10 does not belong to the alternative SoftAPNW to a parent statewhere the printer 10 operates as a parent station of the alternativeSoftAPNW.

Moreover, since the printer 10 has not activated the alternative SoftAPat the time of T16, even when a Probe Req. signal including the SSID“YYY” used in the alternative SoftAPNW is received, the printer 10 doesnot transmit a response signal to the Probe Req. signal (that is, aProbe Res. signal). Therefore, since the terminal apparatus 50 does notreceive a response signal from the printer 10 even after a prescribedperiod of time lapses from the transmission of the Probe Req. signal inT16, in T24, the terminal apparatus 50 once again transmits the ProbeReq. signal including the SSID “YYY” to the printer 10.

The printer 10 has activated the alternative SoftAP at the time of T24or, that is, when the printer 10 once again receives the Probe Req.signal including the SSID “YYY” from the terminal apparatus 50.Therefore, in T26, the printer 10 transmits a Probe Res. signalincluding the SSID “YYY” to the terminal apparatus 50.

In T32, the terminal apparatus 50 sequentially transmits aDisassociation signal to the normal AP 100 using the normal APNW.Accordingly, the normal AP connection between the terminal apparatus 50and the normal AP 100 is cut off. In the present embodiment, theterminal apparatus 50 is capable of establishing a wireless connectiononly with one apparatus. In addition, since the terminal apparatus 50needs to establish a SoftAP connection with the printer 10 in a processto be described later, in T32, the terminal apparatus 50 cuts off thenormal AP connection with the normal AP 100.

Subsequently, in T36, the printer 10 receives an Association Req. signalincluding the SSID “YYY” from the terminal apparatus 50 and, in T38, theprinter 10 transmits an Association Res. signal including the SSID “YYY”to the terminal apparatus 50. In T40, the printer 10 performscommunication of various signals (for example, a 4-way handshake) withthe terminal apparatus 50 and establishes a SoftAP connection with theterminal apparatus 50. Accordingly, the printer 10 can form thealternative SoftAPNW to which both the printer 10 being a parent stationand the terminal apparatus 50 being a child station belong.

In T42, using the alternative SoftAPNW, the printer 10 receives normalAP setting information 150 in a memory of the terminal apparatus 50 fromthe terminal apparatus 50. As described above, the normal AP settinginformation 150 is information currently being used in the normal APNWand includes the SSID “ZZZ”, the password “CCC”, and the like.

In T44, the printer 10 sets the normal AP setting information 150.Specifically, the printer 10 stores the normal AP setting information150 in the normal AP setting area 46.

Subsequently, in T46 shown in FIG. 3, the printer 10 transmits a ProbeReq. signal including the SSID “ZZZ” to the normal AP 100 and, in T48,the printer 10 receives a Probe Res. signal including the SSID “ZZZ”from the normal AP 100.

In T50, the printer 10 performs communication of various signals(Association Req./Res. signals, a 4-way handshake, and the like) withthe normal AP 100 and establishes a normal AP connection with the normalAP 100. Accordingly, the printer 10 can join, as a child station, anormal APNW formed by the normal AP 100 being a parent station. Inaddition, the printer 10 can perform various communications with otherapparatuses via the normal AP 100. For example, via the normal AP 100,the printer 10 can receive an image file representing an image from theother apparatuses and cause the print performing unit 16 to print theimage.

In T52, the printer 10 transmits a setting result to the terminalapparatus 50 using the alternative SoftAPNW. In the present case, thesetting result indicates that the setting of the normal AP settinginformation 150 at the printer 10 has been successful, that is, a normalAP connection between the printer 10 and the normal AP 100 has beensuccessfully established. Supposing that a normal AP connection betweenthe printer 10 and the normal AP 100 is not successfully established, asetting result indicating a failure is transmitted from the printer 10to the terminal apparatus 50.

In a case where the terminal apparatus 50 receives a setting result fromthe printer 10 using the alternative SoftAPNW, the setting result isdisplayed in T54. The user can be informed that the setting of thenormal AP setting information 150 at the printer 10 has been successfulby viewing the setting result.

Subsequently, in T56, the printer 10 transmits a Deauthentication signalto the terminal apparatus 50 and, in T60, the printer 10 receives aDisassociation signal from the terminal apparatus 50. Accordingly, theprinter 10 cuts off the SoftAP connection with the terminal apparatus50.

In T64, the printer 10 stops the alternative SoftAP. Specifically, theprinter 10 erases the alternative SoftAP setting information 40 in theparent station setting area 44. Accordingly, the printer 10 causes thealternative SoftAPNW to disappear. The operating state of the printer 10shifts from the parent state where the printer 10 operates as the parentstation of the alternative SoftAPNW to the state where the printer 10does not belong to the alternative SoftAPNW.

In T66, the terminal apparatus 50 performs communication of varioussignals to once again establish the normal AP connection with the normalAP 100 and joins the normal APNW as a child station. Accordingly, astate is created where the normal AP 100 being the parent station, theprinter 10 being a child station, and the terminal apparatus 50 being achild station all belong to the normal APNW. As a result, for example,the printer 10 can receive an image file from the terminal apparatus 50via the normal AP 100 and perform printing.

(Effect of First Embodiment)

In the case where the printer 10 determines that the SSID “YYY” in theProbe Req. signal received from the terminal apparatus 50 matches theSSID “YYY” in the memory 34 (YES in T18), the printer 10 causes theoperating state of the printer 10 to shift from the state where theprinter 10 does not belong to the alternative SoftAPNW to the parentstate of the alternative SoftAPNW (T22 shown in FIG. 2). Then, theprinter 10 forms the alternative SoftAPNW to which both the printer 10being a parent station and the terminal apparatus 50 being a childstation belong (T36 to T40). On the other hand, in the case where theprinter 10 determines that the SSID in the Probe Req. signal receivedfrom the terminal apparatus 50 does not match the SSID “YYY” in thememory 34 (NO in T18), the operating state of the printer 10 ismaintained in the state where the printer 10 does not belong to thealternative SoftAPNW. That is, the printer 10 may not need to perform aprocess for stopping the initial SoftAP, a process for activating thealternative SoftAP, and the like. As a result, a processing load on theprinter 10 can be prevented from increasing unnecessarily.

Furthermore, in the case where the printer 10 forms the alternativeSoftAPNW, the printer 10 uses the alternative SoftAPNW to receive thenormal AP setting information 150 from the terminal apparatus 50 (T42shown in FIG. 2) and uses the normal AP setting information 150 tobelong to the normal APNW (T46 to T50 shown in FIG. 3). Accordingly, theprinter 10 can perform wireless communication via the normal AP 100using the normal APNW.

In particular, the present embodiment adopts the specific configurationdescribed above in which the initial SoftAP is activated when power ofthe printer 10 is turned on. A configuration of a comparative examplemay conceivably be adopted in which initial SoftAP setting information38 instead of alternative SoftAP setting information 40 is registered inadvance to the setting application 200. In this case, the terminalapparatus 50 can use the initial SoftAP setting information 38 to join,as a child station, the initial SoftAPNW in which the printer 10operates as a parent station and, subsequently, use the initial SoftAPNWto transmit the normal AP setting information 150 to the printer 10.According to the configuration of the comparative example, the printer10 may not need to stop the initial SoftAP and may not need not activatethe alternative SoftAP. However, as described above, the initialSoftAPNW using the initial SoftAP setting information 38 uses anauthentication scheme and a coding scheme having relatively low securitylevels. Therefore, in the initial SoftAPNW in which the initial SoftAPsetting information 38 is used, security is difficult to be ensured andthere is a risk that information may be leaked to a third party viaother apparatuses participating in the initial SoftAPNW. Contrary tothis, the present embodiment adopts a configuration in which analternative SoftAP is activated using the alternative SoftAP settinginformation 40 instead of the initial SoftAP. In the alternativeSoftAPNW using the alternative SoftAP, the alternative SoftAP settinginformation 40 including an authenticating scheme and a coding schemehaving relatively high security levels may be used. That is, in thepresent embodiment, the printer 10 can use the alternative SoftAPNW witha higher security level than the initial SoftAPNW.

(Correspondence)

The printer 10, the terminal apparatus 50, and the normal AP 100 are,respectively, examples of a “communication apparatus”, an “externalapparatus”, and a “specific access point”. The alternative SoftAPNW, theinitial SoftAPNW, and the normal APNW are, respectively, examples of a“first wireless network”, “second wireless network”, and a “specificwireless network”. The SSID “YYY” is an example of a “specific characterstring”, a “specific wireless identifier”, and a “first wirelessidentifier”. The normal AP setting information 150 and the alternativeSoftAP are, respectively, examples of “specific wireless settinginformation” and an “access point function”. The Probe Req. signal inT16, the Probe Req. signal in T24, and the Probe Res. signal in T26shown in FIG. 2 are, respectively, examples of a “first specificsignal”, a “second specific signal”, and a “response signal”. A state ofoperation as the parent station of the alternative SoftAP, a state ofoperation as the child station of the alternative SoftAP, and a state ofoperation of the parent station of the initial SoftAP are, respectively,examples of a “first parent state”, a “child state”, and a “secondparent state”.

Second Embodiment

Differences from the first embodiment will be mainly described. In thepresent embodiment, the printer 10 shifts to a G/O state in the WFDscheme instead of activating an alternative SoftAP.

The wireless I/F 20 further supports the WFD scheme in IEEE 802.11. Thewireless I/F 20 is able to use a second MAC address to shift to the G/Ostate in accordance with the WFD scheme and establish a wirelessconnection (hereinafter, referred to as a “WFD connection”) with otherapparatuses (for example, the terminal apparatus 50). Moreover, theterminal apparatus 50 also supports the WFD scheme. Therefore, theterminal apparatus 50 can join, as a child station (that is, a Clientapparatus (hereinafter, referred to as a “CL apparatus”)), a wirelessnetwork (hereinafter, referred to as a “WFDNW” (an abbreviation of a WFDnetwork)) in which the printer 10 operates as a parent station (that is,a G/O apparatus). Details of the WFD scheme are described in “Wi-FiPeer-to-Peer (P2P) Technical Specification Version 1.1” created by theWi-Fi Alliance. Details of the WFD scheme are also disclosed in USPatent Application Publication No. 2013/0260683, the contents of whichare hereby incorporated by reference into the present application. Inaddition, in the present embodiment, the alternative SoftAP settinginformation 40 includes an SSID “DIRECT-VVV” in place of the SSID “YYY”.

The program 36 of the printer 10 includes WFD setting information 40 inplace of the alternative SoftAP setting information 40. The WFD settinginformation 40 includes the SSID “DIRECT-VVV”, a password “BBB”, and thelike. In addition, the setting application 200 of the terminal apparatus50 includes the WFD setting information 40 in place of the alternativeSoftAP setting information 40.

(Processes of Respective Devices 10, 50, 100, and the Like: FIGS. 4 and5)

Next, contents of the respective processes performed by the printer 10and the like will be described with reference to FIGS. 4 and 5. In aninitial state shown in FIG. 4, the terminal apparatus 50 does notcurrently belong to the normal APNW. However, since the terminalapparatus 50 has previously belonged to the normal APNW, the terminalapparatus 50 stores the normal AP setting information 150.

T110 to T114 are respectively similar to T10 to T14 shown in FIG. 2. InT116, the printer 10 receives a Probe Req. signal including a characterstring “DIRECT-” from the terminal apparatus 50. The character string“DIRECT-” is a character string indicating that the terminal apparatus50 supports the WFD scheme. In addition, the Probe Req. signal includingthe character string “DIRECT-” is a signal for searching for otherapparatuses that support the WFD scheme. As described above, the printer10 supports the WFD scheme. Therefore, in T118, the printer 10 transmitsa Probe Res. signal including the character string “DIRECT-” to theterminal apparatus 50.

In T120, the terminal apparatus 50 reads out the SSID “DIRECT-VVV”included in the WFD setting information 40 in the setting application200 and transmits an Invitation Req. signal including the SSID“DIRECT-VVV” to the printer 10. The Invitation Req. signal is a signalfor requesting the printer 10 to form a WFDNW.

In a case where the printer 10 receives the Invitation Req. signalincluding the SSID “DIRECT-VVV” from the terminal apparatus 50, in T122,the printer 10 determines whether or not the SSID “DIRECT-VVV” in theInvitation Req. signal matches the SSID “DIRECT-VVV” included in the WFDsetting information 40 in the memory 34. In a case where the SSID“DIRECT-VVV” in the Invitation Req. signal matches the SSID “DIRECT-VVV”in the memory 34 (YES in T122), the printer 10 proceeds to T124.

On the other hand, a case is assumed, where a state where, for example,the terminal apparatus 50 operates as a G/O apparatus and has formed aWFDNW. In the WFDNW, an SSID that differs from the SSID “DIRECT-VVV” isbeing used. In case where the user of the terminal apparatus 50 desiresto have the printer 10 join the WFDNW, an operation for this purpose isperformed on the terminal apparatus 50. In this case, the printer 10 mayreceive an Invitation Req. signal that includes the different SSID. Insuch a state, the printer 10 determines that the SSID in the InvitationReq. signal does not match the SSID “DIRECT-VVV” in the memory 34 (NO inT122) and ends the processing shown in FIG. 4 without performing theprocesses of T124 and thereafter. In this case, the operating state ofthe printer 10 is maintained in a state where the printer 10 does notbelong to the WFDNW identified by the SSID “DIRECT-VVV”.

In T124, the printer 10 transmits an Invitation Res. signal to theterminal apparatus 50. T126 is similar to T20 shown in FIG. 2. Next, inT128, the printer 10 causes the operating state of the printer 10 toshift from a device state (that is, a state in which the printer 10 doesnot belong to the WFDNW) to the G/O state. Specifically, the printer 10stores the WFD setting information 40 included in the program 36 in theparent station setting area 44. Accordingly, the operating state of theprinter 10 shifts from the state where the printer 10 does not belong tothe WFDNW to a parent state where the printer 10 operates as a parentstation of the WFDNW. T136 to T140 are similar to T36 to T40 shown inFIG. 2 with exception of the use of the SSID “DIRECT-VVV” and theestablishment of a WFD connection instead of a SoftAP connection.Accordingly, the printer 10 can form the WFDNW to which both the printer10 being a parent station (that is, a G/O apparatus) and the terminalapparatus 50 being a child station (that is, a CL apparatus) belong.T142 is similar to T42 shown in FIG. 2 with exception of the use of theWFDNW instead of the SoftAPNW. T144 is similar to T44 shown in FIG. 2.

T146 to T154 shown in FIG. 5 are respectively similar to T46 to T54shown in FIG. 3. T156 to T160 are similar to T56 to T60 shown in FIG. 3with exception of a WFD connection being cut off instead of a SoftAPconnection being cut off. In T162, the terminal apparatus 50 causes theoperating state of the terminal apparatus 50 to shift from a CL state tothe device state. In T164, the printer 10 causes the operating state ofthe printer 10 to shift from the G/O state to the device state.Accordingly, the printer 10 causes the WFDNW to disappear.

(Effect of Second Embodiment)

In the present embodiment, in a case where it is determined that theSSID in the Invitation Req. signal received from the terminal apparatus50 does not match the SSID “DIRECT-VVV” in the memory 34 (NO in T122 inFIG. 4), the operating state of the printer 10 is maintained in a statewhere the printer 10 does not belong to the WFDNW. That is, the printer10 may not need to perform a process for stopping the initial SoftAP, aprocess for shifting to the G/O state, and the like. As a result, aprocessing load on the printer 10 can be prevented from increasingunnecessarily. In addition, in a case where the terminal apparatus 50once again joins the normal APNW after the various processes shown inFIG. 5 end, the printer 10 can perform wireless communication with theterminal apparatus 50 via the normal AP 100 using the normal APNW.

(Correspondence)

The WFDNW is an example of a “first wireless network”. The SSID“DIRECT-VVV” is an example of a “specific character string”, a “specificwireless identifier”, and a “first wireless identifier”. The InvitationReq. signal in T120 shown in FIG. 4 is an example of a “first specificsignal”. The device state, the G/O state, and the CL state are,respectively, examples of a “first non-belonging state”, a “first parentstate”, and a “child state”.

Third Embodiment

Differences from the first embodiment will be mainly described. Theterminal apparatus 50 supports a SoftAP function and is capable ofactivating a SoftAP using the alternative SoftAP setting information 40in the setting application 200, establish a SoftAP connection with theprinter 10, and form an alternative SoftAPNW to which both the terminalapparatus 50 being a parent station and the printer 10 being a childstation belong. Both a MAC address for establishing a normal APconnection and a MAC address for establishing a SoftAP connection areassigned to the terminal apparatus 50. Therefore, the terminal apparatus50 is capable of simultaneously performing both wireless communicationusing the normal AP connection and wireless communication using theSoftAP connection.

The printer 10 can join the alternative SoftAPNW formed by the terminalapparatus 50 as a child station without activating an alternativeSoftAP. The memory 34 of the printer 10 includes a child station settingarea 48. The child station setting area 48 is an area in which, in astate where the printer 10 operates as the child station of thealternative SoftAPNW, the alternative SoftAP setting information 40 tobe used in the alternative SoftAPNW is stored.

(Processes of Respective Devices 10, 50, 100, and the Like; FIG. 6)

Next, contents of the respective processes performed by the printer 10and the like will be described with reference to FIG. 6. An initialstate in FIG. 6 is similar to the initial state shown in FIG. 2. T210 toT214 are respectively similar to T10 to T14 shown in FIG. 2.

In T216, the terminal apparatus 50 activates the alternative SoftAPusing the alternative SoftAP setting information 40 in the settingapplication 200. Next, in T218, the terminal apparatus 50 reads out theSSID “YYY” included in the alternative SoftAP setting information 40 inthe setting application 200 and transmits a Beacon signal including theSSID “YYY” to the printer 10. The Beacon signal is a signal forsearching for apparatuses that should join the alternative SoftAPNWformed by the terminal apparatus 50.

In a case where the printer 10 receives the Beacon signal including theSSID “YYY” from the terminal apparatus 50, in T220, the printer 10determines whether or not the SSID “YYY” in the Beacon signal matchesthe SSID “YYY” in the memory 34. In a case where the SSID “YYY” in theBeacon signal matches the SSID “YYY” in the memory 34 (YES in T220), theprinter 10 proceeds to T222.

On the other hand, a situation will be assumed here where, for example,the terminal apparatus 50 has activated a SoftAP using another settinginformation in another application program instead of using thealternative SoftAP setting information 40 in the setting application200. In this case, the terminal apparatus 50 transmits a Beacon signalincluding an SSID included in the other setting information (that is, anSSID other than “YYY”). Therefore, the printer 10 may receive the Beaconsignal that includes the different SSID from the terminal apparatus 50.In such a state, the printer 10 determines that the SSID in the Beaconsignal does not match the SSID “YYY” in the memory 34 (NO in T220) andends the processing shown in FIG. 6 without performing the processes ofT222 and thereafter. In this case, the operating state of the printer 10is maintained in the state where the printer 10 does not belong to thealternative SoftAPNW identified by the SSID “YYY”.

T222 is similar to T20 shown in FIG. 2. Moreover, in a modification, theprinter 10 may maintain a state where an initial SoftAP is activewithout performing T222. Subsequently, in T224, the printer 10 transmitsan Association Req. signal including the SSID “YYY” to the terminalapparatus 50 and, in T225, the printer 10 receives an Association Res.signal including the SSID “YYY” from the terminal apparatus 50. In T226,the printer 10 performs communication of various signals (for example, a4-way handshake) with the terminal apparatus 50 and establishes a SoftAPconnection with the terminal apparatus 50. At this occasion, the printer10 stores the alternative SoftAP setting information 40 in the childstation setting area 48. Accordingly, the operating state of the printer10 shifts from the state where the printer 10 does not belong to thealternative SoftAPNW to a child state where the printer 10 operates as achild station of the alternative SoftAPNW. As a result, the printer 10can form the alternative SoftAPNW to which both the printer 10 being achild station and the terminal apparatus 50 being a parent stationbelong.

T228 is similar to T42 shown in FIG. 2. In T230, the printer 10 receivesa Deauthentication signal from the terminal apparatus 50 and, in T234,the printer 10 transmits a Disassociation signal to the terminalapparatus 50. In T238, the terminal apparatus 50 stops the alternativeSoftAP. Accordingly, the terminal apparatus 50 causes the alternativeSoftAPNW to disappear.

T244 to T250 are respectively similar to T44 shown in FIG. 2 to T50shown in FIG. 3. In T248, the printer 10 displays a setting resultindicating that the setting of the normal AP setting information 150 hasbeen successful on the display unit 14.

(Effect of Third Embodiment)

According to the present embodiment, in the case where it is determinedthat the SSID in the Beacon signal received from the terminal apparatus50 does not match the SSID “YYY” in the memory 34 (NO in T220), theoperating state of the printer 10 is maintained in the state where theprinter 10 does not belong to the alternative SoftAPNW. That is, theprinter 10 may not need to perform a process for stopping the initialSoftAP, a process for establishing the SoftAP connection of T224 toT226, and the like. As a result, a processing load on the printer 10 canbe prevented from increasing unnecessarily. Further, the printer 10 canperform wireless communication via the normal AP 100 using a normalAPNW. Moreover, in the present embodiment, the Beacon signal in T218shown in FIG. 6 is an example of a “first specific signal”.

(First modification) In the first to third embodiments described above,the printer 10 may not receive the normal AP setting information 150from the terminal apparatus 50 and may not establish a normal APconnection with the normal AP 100 using an alternative SoftAPNW or aWFDNW. In this case, the printer 10 may receive an image filerepresenting an image from the terminal apparatus 50 using analternative SoftAPNW or a WFDNW and perform printing of the image. Thatis, a “communication apparatus” may not perform “receiving specificwireless setting information from the external apparatus” and “belongingto the specific wireless network by using the specific wireless settinginformation”.

(Second modification) While the printer 10 stops the alternative SoftAP(T64 shown in FIG. 3) in the first embodiment described above, theprinter 10 may maintain the state where the alternative SoftAP isactive. In this case, the printer 10 can maintain a state wherecommunication with the terminal apparatus 50 can be performed using thealternative SoftAPNW. That is, a “communication apparatus” may notperform “causing the first wireless network to disappear”.

(Third modification) In the first to third embodiments described above,the printer 10 may not activate an initial SoftAP when power is turnedon. That is, a “communication apparatus” may not perform “causing theoperating state of the communication apparatus to shift from a secondnon-belonging state to a second parent state”.

(Fourth modification) In the third embodiment described above, thefollowing process may be performed in place of T216 to T220 shown inFIG. 6. After activating the setting application 200 in T214, the userfurther performs a predetermined operation on the printer 10. In thiscase, the printer 10 transmits a Probe Req. signal that does not includean SSID to the terminal apparatus 50. The terminal apparatus 50activates an alternative SoftAP in a case where the terminal apparatus50 receives the Probe Req. signal that does not include an SSID from theprinter 10. Subsequently, the printer 10 once again transmits the ProbeReq. signal that does not include an SSID to the terminal apparatus 50and receives a Probe Res. signal including the SSID “YYY” from theterminal apparatus 50. The printer 10 determines whether or not the SSIDin the Probe Res. signal matches the SSID “YYY” in the memory 34. In acase where the SSID in the Probe Res. signal matches the SSID “YYY” inthe memory 34, the printer 10 proceeds to T222. In the presentmodification, the Probe Res. signal is an example of a “first specificsignal”.

(Fifth modification) In the second embodiment described above, in T120shown in FIG. 4, the printer 10 may receive a G/O Negotiation Req.signal including the SSID “DIRECT-VVV” from the terminal apparatus 50instead of an Invitation Req. signal. In T122, the printer 10 maydetermine whether or not the SSID in the G/O Negotiation Req. signalmatches the SSID “DIRECT-VVV” in the memory 34. In a case where the SSIDin the G/O Negotiation Req. signal matches the SSID “DIRECT-VVV” in thememory 34 (YES in T122), in T124, the printer 10 transmits a G/ONegotiation Res. signal to the terminal apparatus 50 instead of anInvitation Res. signal. In T128, as a result of the G/O Negotiation, theprinter 10 may shift to a G/O state or to a CL state. In the presentmodification, the G/O Negotiation Req. signal is an example of a “firstspecific signal”.

(Sixth modification) The “communication apparatus” is not limited to aprinter and may be, for example, a scanner or a PC. That is, the“communication apparatus” includes all apparatuses capable ofcommunicating with other apparatuses.

(Seventh embodiment) In the respective embodiments described above, therespective processes shown in FIGS. 2 to 6 are realized by the CPU 32 ofthe printer 10 executing a program (that is, software). Alternatively,at least one of the respective processes may be realized by hardwaresuch as a logic circuit.

What is claimed is:
 1. A communication apparatus comprising: acontroller configured to perform: receiving a first specific signalincluding a specific wireless identifier from an external apparatus, thespecific wireless identifier identifying a first wireless network; in acase where the first specific signal including the specific wirelessidentifier is received from the external apparatus, shifting anoperating state of the communication apparatus from a first non-parentstate to a first parent state, the communication apparatus not operatingas a parent station in the first non-parent state, and the communicationapparatus operating as a parent station in the first parent state; andforming the first wireless network to which both the communicationapparatus being the parent station and the external apparatus being achild station belong after the operating state of the communicationapparatus is shifted to the first parent state.
 2. The communicationapparatus as in claim 1, wherein the controller is configured to furtherperform: receiving specific wireless setting information from theexternal apparatus by using the first wireless network in a case wherethe first wireless network is formed, the specific wireless settinginformation being currently used in a specific wireless network formedby a specific access point, the external apparatus satisfying either onecondition of currently belonging to the specific wireless network andhaving previously belonged to the specific wireless network; andbelonging to the specific wireless network by using the specificwireless setting information in a case where the specific wirelesssetting information is received from the external apparatus.
 3. Thecommunication apparatus as in claim 2, wherein the controller isconfigured to further perform: causing the first wireless network to beunavailable after the specific wireless setting information is receivedfrom the external apparatus.
 4. The communication apparatus as in claim1, wherein a response signal is not sent to the external apparatus inresponse to receiving the first specific signal, and the controller isconfigured to further perform: sending a response signal to the externalapparatus in response to receiving a second specific signal from theexternal apparatus after the first specific signal has been received. 5.The communication apparatus as in claim 1, wherein the first specificsignal is a Probe Request signal, and the operating state of thecommunication apparatus is shifted from the first non-parent state tothe first parent state by being shifted from a state in which an accesspoint function is inactive to a state in which the access point functionis active, the access point function being a function by which thecommunication apparatus operates as an access point of the firstwireless network.
 6. The communication apparatus as in claim 1, whereinthe first specific signal is an Invitation Request signal in accordancewith Wi-Fi Direct (registered trademark) scheme, and the operating stateof the communication apparatus is shifted from the first non-parentstate to the first parent state by being shifted from a device state inaccordance with the Wi-Fi Direct scheme to a Group Owner state inaccordance with the Wi-Fi Direct scheme.
 7. The communication apparatusas in claim 1, wherein the controller is configured to further perform:causing the operating state of the communication apparatus to shift froma second non-parent state to a second parent state, when power of thecommunication apparatus is turned on, the communication apparatus notoperating as a parent station in the second non-parent state, and thecommunication apparatus operating as a parent station of a secondwireless network identified by a second wireless identifier in thesecond parent state, and wherein the first specific signal is receivedfrom the external apparatus while the operating state of thecommunication apparatus is the second parent state.
 8. The communicationapparatus as in claim 1, wherein the controller is configured to furtherperform: determining whether the specific wireless identifier in thefirst specific signal is an SSID (Service Set Identifier) in accordancewith a predetermined rule, wherein in a case where the first specificsignal including the specific wireless identifier is received from theexternal apparatus and it is determined that the specific wirelessidentifier is the SSID in accordance with the predetermined rule, theoperating state of the communication apparatus is shifted from the firstnon-parent state to the first parent state.
 9. The communicationapparatus as in claim 1, wherein the controller is configured to furtherperform: determining whether the operating state of the communicationapparatus is to be shifted from the first non-parent state to the firstparent state, in a case where the first specific signal is received fromthe external apparatus, and wherein in a case where the first specificsignal including the specific wireless identifier is received from theexternal apparatus and it is determined that the operating state of thecommunication apparatus is to be shifted from the first non-parent stateto the first parent state, the operating state of the communicationapparatus is shifted from the first non-parent state to the first parentstate.
 10. A non-transitory computer readable having instructions storedthereon that, when executed by a computing device of a communicationapparatus, cause the communication apparatus to: receive a specificsignal including a specific wireless identifier from an externalapparatus, the specific wireless identifier identifying a wirelessnetwork; in a case where the specific signal including the specificwireless identifier is received from the external apparatus, shifting anoperating state of the communication apparatus from a non-parent stateto a parent state, the communication apparatus not operating as a parentstation in the non-parent state, and the communication apparatusoperating as a parent station in the parent state; and forming thewireless network to which both the communication apparatus being theparent station and the external apparatus being a child station belongafter the operating state of the communication apparatus is shifted tothe parent state.